ONE
var arr = [{ name: "Poet", age: 20 }, { name: "刘现挪", age: 19 }, { name: "妙妙", age: 20 }]
for (var i in arr) {
    var a = arr[i].name
    var b = arr[i].age
    console.log('姓名:' + a + '年龄:' + b);
}

TWO
function num(num1, num2) {
    let a = num1 * num2
    console.log(a);
}
num(3, 5)

THREE
let a = (Str1, Str2) => {
    console.log(`我叫${Str1}今年${Str2}`);
}
a('Poet', 20)

FOUR
const fs = require('fs');
fs.readFile('./num.txt', 'utf8', (error, data) => {
    if (!err) {
        let b = JSON.parse(data);
        console.log(b.data);
        let c = b.data;
        var d = 0;
        for (let i = 0; i < c.length; i++) {
            d = d + c[i];
        }
        console.log(d);
    } else {
        throw err
    }
})